(TNS) - This week marks 30 years since the massive 6.9 magnitude Loma Prieta earthquake hit the Bay Area, killing 63 people, injuring nearly 4,000 and causing extensive damage that left thousands homeless.

Generally, people in this part of the state are not too concerned about quakes. Should they be?

Earthquakes, big and small, are a common occurrence in California. Residents hear reports of them all the time – most recently the 4.5 magnitude quake that hit near Pleasant Grove on Monday. The reports are usually just far enough away from the Yuba-Sutter area that residents tend to think things like that won’t happen here.

(TNS) — California Gov. Gavin Newsom is set to unveil the state's new earthquake early warning app, MyShake, at 11 a.m. Thursday, available on iOS and Android on the 30th anniversary of the magnitude 6.9 Loma Prieta earthquake. The announcement will be streamed live.

How much warning would MyShake have provided if an earthquake warning system were available in 1989?

The California Earthquake Authority gained 23,861 earthquake insurance policies following the magnitude 6.4 and 7.1 earthquakes and aftershocks that struck on unnamed faults near Ridgecrest beginning on the July 4 holiday.

That’s the second-largest monthly net increase in the 23-year history of the CEA, a not-for-profit, privately funded, publicly managed organization.

(TNS) — More than 500,000 people have downloaded Los Angeles County’s new ShakeAlertLA app to warn them of impending earthquakes.

So when the two strongest earthquakes in almost two decades hit Southern California this month, those residents were surprised by what they saw on their smartphones: nothing.

Officials were quick to explain to outraged app users that the shaking in the county wasn’t strong enough to trigger an alert.

The powerful Mojave Desert earthquakes that rocked California ended a years-long lull in major seismic activity and raised new interest in an early warning system being developed for the West Coast.

The ShakeAlert system is substantially built in California and overall is about 55% complete, with much of the remaining installation of seismic sensor stations to be done in the Pacific Northwest, said Robert de Groot of the U.S. Geological Survey.

(TNS) - For the second consecutive day, a major earthquake shook Southern California and was felt far beyond, stopping the NBA’s Summer League games in Las Vegas, forcing the evacuation of rides at Disneyland in Anaheim, and reminding residents that the state is always on unstable ground and destined for more.

It registered a magnitude of 7.1 on Friday night and was the strongest earthquake to hit the state in two decades, causing fires in the small town of Ridgecrest (population 29,000), and sending shock waves felt more than 300 miles away in all directions – Sacramento, Phoenix, Mexico.

RIDGECREST, Calif. — Crews in Southern California assessed damage to cracked and burned buildings, broken roads, leaking water and gas lines and other infrastructure Saturday after the largest earthquake the region has seen in nearly 20 years jolted an area from Sacramento to Las Vegas to Mexico.

No fatalities or major injuries were reported after Friday night’s 7.1-magnitude earthquake. But warnings by seismologists that large aftershocks were expected to continue for days — if not weeks — prompted further precautions.

The U.S. Geological Survey a magnitude 5.5 earthquake has hit near the Pacific coast of Northern California.

The agency says the earthquake struck at 8:53 p.m. on Saturday at a spot 17.3 miles southwest of Scotia, a town of 850 people.

The U.S. Geological Survey confirmed a magnitude 3.2 earthquake hit central California.

The agency says the earthquake hit a spot 11.4 miles southwest of Darwin, a town of about 36 people, at 6:48 p.m.

The agency says the earthquake had a depth of 1.2 miles.

Sea level rise, and its perils, is often associated with the East Coast. But California communities along the coast that don’t prepare for what’s ahead could be inviting disasters of the magnitude not yet seen in the state.

A report by the United States Geological Survey Climate Impacts and Coastal Processes Team suggests that future sea level rise, in combination with major storms like the ones the state is experiencing now, could cause more damage than wildfires and earthquakes.

This is the first study that looks not just at sea level rise in California, but also sea level rise, along with a major storm to assess total risk to coastal communities.